This invention relates to electrical circuit means for use in analogue display and/or control systems.
It is well known that an array of light emitting diodes (hereinafter referred to as "LED") can be used to provide a visual indication of the magnitude of an electrical parameter, typically voltage. The number, or position within the array, of LED's that emit is determined by the magnitude of the input voltage.
Hitherto such analogue display systems have used digital logic circuitry (such as shift-register, counter, or decoder networks) to turn the individual LED's on and off, with an analogue-to-digital convertor circuit to interface with the analogue voltage input.
This method is needlessly complex since both input and output are analogue, whilst the signal processing in between is digital. This complexity leads to high costs.